I saw somewhere that BMW is debating on the use of CF roof panels & hardware (along with the roof supporting arms) to lower weight. As opposed to the Steel pieces for the upcoming E93/M3. That would be SWEET!
I try to find the source and post it....

His CF roof is an overlay btw. It's not a replacement. I'm sure a skilled person could install a CF overlay on your E93 if you so desired. It's a good question for the best BMW aftermarket shop in your area or if you are so inclined you could venture to try it yourself. Good luck.